Trivia

It was stated by Eryn in the Evil Goddess path of Fairy Fencer F ADVENT DARK FORCE that if a fencer passes away, then the fairy would die as well. An example would include:

Galdo in the Vile God route, who was fatally injured by Bernard. Before dying, he even stated that if he dies, Marissa will disappear as a result.

Sherman in more than one instance, where in the Goddess route, when Sherman fused with the Vile God, Ryushin's presumably faded from existence. In the Evil God route, after Noie killed Sherman, Ryushin appears to be shutting down afterwards.

Tiara in the first timeline. When she dies, Eryn comments that she can no longer sense Cui.